A = readmatrix ('CD_500_750nm.txt')

x = A(:,1)
y = -A(:,4)*100


hold on
plot(x,y,LineWidth=1,Color=[0 0 0])
xlim([500,750])
xticks(500:50:750)
ylim([-17,5])
yticks([-15:5:0])
xlabel('Wavelength [nm]')
ylabel('CPGE dichroism [%]')
set(gca,'XMinorTick','on','YMinorTick','on')
set(gca,'box','on','Xcolor',[0 0 0],'Ycolor',[0 0 0])
hold off
box on
set(gcf,'Position',[0, 0, 192, 200])